Encryption

Encryption is a technique used to keep digital information private by turning readable data (plaintext) into a coded form called ciphertext. Only people with the right tools or keys can turn the ciphertext back into its original form (decryption), making sure unauthorized individuals can’t access the information.

Encryption is essential for protecting emails, online transactions, and private messages from hackers and eavesdroppers. Most devices and online services rely on strong encryption to keep user data safe. Different encryption methods exist, offering varying levels of security. Most systems use cryptographic keys—secret codes used for locking (encrypting) and unlocking (decrypting) the data. How these keys are managed depends on the particular encryption method. Some systems, like the Advanced Encryption Standard (AES), are widely trusted today, while simple schemes like the Caesar cipher are now easy to break.

Modern encryption often uses “asymmetric” methods, in which two different keys are used: a public key shared openly for encrypting data, and a private key kept secret for decrypting it. For instance, if Bob wants to receive a secure message from Alice, he shares his public key with her. Alice uses this key to encrypt her message; only Bob can decrypt it using his private key. Even if the message is intercepted, the content remains confidential as long as Bob's private key is secure.

Encryption constantly evolves to defend against new threats, including powerful computers and potential quantum attacks, making it a cornerstone of digital security.